Infectious Diseases Affecting the Respiratory System: COVID-19 Pandemic Update

Flashcards covering key vocabulary and concepts from the lecture notes on infectious diseases, focusing on COVID-19, its variants, and comparisons to other viral outbreaks.

COVID-19 (aka: nCoV, SARS-CoV-2)

A coronavirus disease with a presumed country of origin in Wuhan, China, with the timeline of 2019-present. Treatment includes supportive care, antivirals, antibodies, supplemental O2 ventilation, steroids, and proning. Prevention includes masking/social distancing and vaccines. All ages are susceptible, but the elderly, immunocompromised, & those with CVD are most likely to develop severe illness. Incubation period is 5-14 days.

SARS

Viral strain with presumed country of origin in Guangdong province, China.The timeline was 2002-2003 (no new cases since 2004). Antivirals & steroids worked for some patients; Vaccine ready just as pandemic ended. Few asymptomatic cases allowed effective containment. Targets elderly & the immunocompromised. Incubation period: 5-14 days

MERS-CoV

Viral strain (Presumed country of origin), Saudi Arabia with a timeline of 2012–2014 (still circulating in camels). Treatment involves supportive care; proper hygiene if caring for infected individuals; hand washing after contact with camels; avoiding unpasteurized camel products. Vaccine development in progress. Human-to-human transmission is limited to close contact. Exception: 1 super spreader in S. Korea infected 186 people. Incubation period: 5-7 days

Interferon blocking proteins

Remove critical component of innate immunity that targets viruses

Activation of inflammation via cytokines

Can lead to pneumonia, ARDS, cardiomyopathy, and renal failure

COVID-19 Variants

Mutations cause slight changes in viral spike proteins leading to increased transmissibility, rapid circulation in populations with low vaccination rates, increased chances of new variants forming, reduced effectiveness of monoclonal antibody treatments, ability to infect those previously infected with other variants and presumed susceptibility to current vaccines.

Measles herd immunity threshold

95%

Polio herd immunity threshold

80%

COVID-19 herd immunity threshold

TBD (70 - 85% proposed)

All currently available COVID-19 vaccines

Prevent serious disease/death

Preliminary COVID-19 U.S. data January – June 2021

99.2% of deaths occurred in unvaccinated people